Milling arrangement for tunnel walls

ABSTRACT

The invention relates to a vehicle with a milling arrangement on top. The milling arrangement includes a milling device for grinding an upper tunnel wall surface like tunnel ceilings of traffic tunnels. Such a vehicle with the milling arrangement according to the invention is suitable for treating tunnel walls such that a desired surface roughness and the removal of carbon black results. This assures that a lining which is applied to the tunnel ceiling and wall surface is sufficiently attached to said surfaces.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of European Application No. EP 05077162.5, filed Sep. 21, 2005, the contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

The present invention relates to a milling arrangement for tunnel walls more particular tunnel ceilings. Such a device is placed on a vehicle to treat tunnel ceilings of traffic tunnels.

As a consequence of exhaust fumes produced by the traffic traveling through tunnels the tunnel walls become covered with a layer of carbon black. In case of a fire in the tunnel the carbon black layer as well as the concrete can start to bum due to very high temperatures which typically occur in case of tunnel fires. In order to improve the safety of existing tunnels it is desirable to apply a fire resistant lining to the tunnel ceiling in order to avoid the hazard of a quick spreading of the fire via the ceiling surface. To assure a sufficient attachment from the fire resistant lining to the existing tunnel ceiling and wall surface, the carbon black has to be removed and the surface has to have a suitable roughness.

SUMMARY OF THE INVENTION

The invention provides a vehicle with a milling arrangement on top, the milling arrangement comprising a milling device for grinding an upper tunnel wall surface. Such a vehicle with the milling arrangement according to the invention is suitable for treating tunnel walls such that a desired surface roughness results.

Preferably the milling device is in height adjustable with respect to the vehicle such that the milling device can be used in an arbitrary tunnel irrespective of the tunnel dimensions.

In a preferred embodiment the milling arrangement comprises a support base and a guide extending in a first direction upwardly from the support base, the milling device being arranged movably along the guide. The support base can be supported by the vehicle, whereas the guide allows for the height adjustment of the milling device with respect to the support base and thus the vehicle.

In a further preferred embodiment the milling device is tiltable around two orthogonal axes which extend orthogonally with respect to the first direction. The fact that the milling device is tiltable allows for the cutting tool to follow closely the shape of the tunnel wall, such that a uniform grinding of the surface is achieved.

In an especially preferred embodiment the guide comprises two parallel guiding tracks each comprising a pair of spaced apart parallel cylindrical members, wherein the space between the cylindrical members is such that a guiding roll can move between them while engaging both cylindrical members. This allows for a tilting movement of the guiding roll between the cylindrical guiding members and thus a tilting of the milling device. The guiding rolls are rotatably mounted on the casing of the milling device such that also a tilting movement around the axis of the rolls of the milling device is possible.

Preferably the guiding rolls have a substantially diabolic shape. This shape delimits the axial movement of the rolls, such that the rolls cannot disengage from the guides.

Preferably the milling arrangement comprises hydraulic means for pressing the milling device against the tunnel wall with a predetermined constant pressure. This improves a uniform grinding of the tunnel surface. In a further preferred embodiment the hydraulic means comprise a hydraulic cylinder which is coupled with one end to the guide and with the other end to the milling device.

In a preferred embodiment the milling device comprises a casing and a rotatable milling drum which is arranged in the casing. Preferably the drum comprises two side plates and a plurality of rods situated on an imaginary cylinder, on which rods a plurality of space apart milling elements are rotatably arranged. Preferably the milling drum is in height adjustable with respect to the casing so as to allow adjustment of the cutting depth of the milling device.

It is envisaged that an upper tunnel wall surface is grinded by placing a milling arrangement as is described hereabove on the fork of a forklift and the forklift is driven through the tunnel.

The invention will be described in more detail in the following description of a preferred embodiment with reference to the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a perspective view of a preferred embodiment of a milling arrangement,

FIG. 2 shows a front elevational view of the arrangement of FIG. 1 in a first state,

FIG. 3 shows a side elevational view of the arrangement of FIG. 1,

FIG. 4 shows a front elevational view of the arrangement of FIG. 1 in a second state,

FIG. 5 shows a side elevational view of the arrangement of FIG. 1 with its milling device in a first tilted state,

FIG. 6 shows a front elevational view of the arrangement of FIG. 1 with its milling device in a second tilted state,

FIG. 7 shows an elevational view of a milling drum suitable for the arrangement of FIG. 1,

FIG. 8 shows a perspective view of a milling element of the milling drum of FIG. 7,

FIG. 9 shows a perspective view of a spacer ring of the milling drum of FIG. 7,

FIG. 10 shows a truck with the milling arrangement of FIG. 1 on top, and

FIG. 11 shows the milling arrangement of FIG. 1 which is lifted by a forklift to treat a tunnel wall.

DETAILED DESCRIPTION OF THE INVENTION

In FIGS. 1-3 is shown a milling arrangement 1. The milling arrangement 1 comprises a support base 2. In the shown example the support base 2 comprise a support frame which is formed of longitudinal beams 3 and lateral beams 4 in this particular example each with a U-shaped cross section. The support base 2 could however also be of a different structure, e.g. out of other types of beams or even formed as a single support plate.

On each side of the base 2 on the beams 3 is placed a pair of two spaced apart tubular guiding elements 5 with a cylindrical outer shape. The tubular guiding elements 5 extend from the support base 2 upwardly and parallel to each other. As is best seen in FIG. 3 between the tubular guiding elements 5 a space 6 is present in which a guiding roll 7 is moveable.

The milling arrangement 1 comprises a milling device 10. The milling device 10 comprises a casing 11 in which the milling tool 20 that will be described in more detail below is rotatably arranged. Suspended under the casing 11 is provided a driving motor 12 for the milling tool 20. The motor 12 drives a shaft of the milling tool 20 by means of a driving belt 13 (see FIG. 1), which is shielded by casing parts 11 a and 11 b.

The abovementioned guiding rolls 7 are rotatably mounted on each side of the casing 11 as is best seen in FIG. 2. The guiding rolls are preferably of diabolic shape.

On each side is provided a hydraulic actuator 14, which is with an upper end 14 a attached to the shaft 15 of the roll 7. The lower end 14 b of the hydraulic actuator 14 is attached to an attachment plate 16 that is fixedly attached to both guiding elements 5 of the pair e.g. by means of bolts and nuts or the like.

In FIGS. 1-3 the actuators 14 are in the retracted state. Consequently the milling device 10 is also in a retracted state. By feeding hydraulic fluid to the actuators 14 they can extended and consequently the milling device 10 is moved upwardly along the guiding elements 5. Accordingly the height of the milling device 10 with respect to the base 2 can be adjusted to a maximum extended state which is shown in FIG. 4. In an extended state the milling tool of the milling device 10 is pressed to the tunnel wall with a certain predetermined constant pressure. Unevenness of the tunnel wall can be compensated for by compression of one or both of the actuators 14 against the pressure of the hydraulic fluid.

As can be seen in FIG. 5 the casing 11 can be tilted around the rotation axis 7 a of the guiding rolls 7. In this way the orientation of the milling tool 20 is automatically adapted to the shape of the tunnel wall, which might typically be arcuate.

In FIG. 6 is shown that the casing 11 is tiltable around an axis which is perpendicular with respect to the rotation axis 7 a of the guiding rolls 7 and perpendicular with respect to the longitudinal direction of the guiding elements 5. The guiding rolls 7 have such a diabolic shape that they provide enough play with respect to the guiding elements 5 that they can be tilted between the guiding elements 5 and thus that the milling device 10 as a whole can be tilted (see FIG. 6). In this tilted state the hydraulic fluid in the actuator 14 on the right in the figure is compressed to a greater extent than in the left actuator 14. An unevenness of the tunnel wall can thus be compensated for.

In FIG. 7 a possible embodiment of the milling tool 20 is shown. The milling tool 20 comprises a milling drum which has two side plates 21 with a circular disc shape. The side plates 21 are interconnected by rods 22. On the rods 22 are provided milling or cutting elements 24 of which a perspective view is shown in FIG. 8. The shown milling or cutting element 24 is a ring shaped element with teeth 24 a. The milling elements 24 are freely rotatable with respect to the rods 22. Between the milling elements 24 are provided distance rings 25 of which a perspective view is shown in FIG. 9. On different rods 22 the milling elements 24 are positioned mutually staggered such that the whole surface of the wall is treated when the drum is rotated. Depending on the surface to be treated the cutting elements can have different shapes, e.g. with differently shaped teeth.

In each side plate 21 is provided an opening 26 through which a driving shaft (not shown) can be inserted. The driving shaft is driven by the motor 12 by means of the belt 13. Preferably the driving shaft has a polygon cross sectional shape and the openings 26 are of a complementary shape with the shaft.

On the lower side of the support 2 U-shaped elements 30 are provided as is e.g. visible in FIG. 1 or 2. These elements 30 are placed at a distance such that a fork 51 of a forklift 50 can be inserted in them (see FIG. 11). The milling arrangement 1 can thus be lifted by a forklift such that it can be placed on a truck or another utility vehicle 40 to drive through a tunnel 41 of which the wall 42 has to be treated, as is shown in FIG. 10.

Another possibility is to drive with the forklift 50 through the tunnel 41 while it lifts the milling arrangement 1. In such a way the tunnel wall 42 can be treated as is shown in FIG. 11. 

1. A vehicle with a milling arrangement on top, the milling arrangement comprising a milling device for grinding an upper tunnel wall surface.
 2. The vehicle according to claim 1, wherein the milling device is in height adjustable with respect to the vehicle.
 3. The vehicle according to claim 1, wherein the milling arrangement comprises a support base and a guide extending in a first direction upwardly from the support base, the milling device being arranged movably along the guide.
 4. The vehicle according to claim 3, wherein the milling device is tiltable with respect to the guide.
 5. The vehicle according to claim 4, wherein the milling device is tiltable around two orthogonal axes which extend orthogonally with respect to the first direction.
 6. The vehicle according to claim 3, in which the guide comprises two parallel guiding tracks.
 7. The vehicle according to claim 6, wherein the milling device is provided with guiding rolls for movement along the guiding tracks.
 8. The vehicle according to claim 7, wherein the guiding tracks each comprise a pair of spaced apart parallel cylindrical members, wherein the space between the cylindrical members is such that a guiding roll can move between them while engaging both cylindrical members.
 9. The vehicle according to claim 7, wherein the guiding rolls have a substantially diabolic shape.
 10. The vehicle according to claim 1, wherein the milling device comprises a casing and a rotatable milling drum which is arranged in the casing.
 11. The vehicle according to claim 10, wherein a motor for driving the milling drum is suspended under the casing.
 12. The vehicle according to claim 1, wherein the milling arrangement comprises hydraulic means for pressing the milling device against the tunnel wall with a predetermined constant pressure.
 13. The vehicle according to claim 12, wherein the hydraulic means comprise a hydraulic actuator which is coupled with one end to the guide and with the other end to the milling device.
 14. The vehicle according to claim 10, wherein the drum comprises two side plates and a plurality of rods situated on an imaginary cylinder, on which rods a plurality of space apart milling elements are rotatably arranged.
 15. The vehicle according to claim 10, wherein the milling drum is in height adjustable with respect to the casing so as to allow adjustment of the cutting depth of the milling device.
 16. A milling arrangement construed and arranged for use in a vehicle according to claim
 1. 17. The milling arrangement according to claim 16, which is adapted to be liftable by a forklift.
 18. A method for grinding an upper tunnel wall surface, wherein a forklift lifts a milling arrangement which is adapted to be liftable by a forklift and wherein the surface is grinded by driving the forklift through the tunnel. 